Arrange the sequence of events at the nmj from first to last. rank the sequence of events at the nmj that initiate an action potential in the muscle fiber, from first to last. view available hint(s) action potential arrives at the axon terminal. action potential arrives at the axon terminal. acetylcholine binds to its receptors on the junctional folds. acetylcholine binds to its receptors on the junctional folds. calcium ions enter the axon terminal. calcium ions enter the axon terminal. synaptic vesicles fuse to membrane of axon terminal. synaptic vesicles fuse to membrane of axon terminal. junctional folds become depolarized. junctional folds become depolarized. action potential is initiated on the sarcolemma. action potential is initiated on the sarcolemma. acetylcholine is released into the synaptic cleft. acetylcholine is released into the synaptic cleft.

Action potential arrives at the axon terminal.  

Calcium ions enter the axon terminal  

Synaptic vesicles fuse to membrane of axon terminal. Acetylcholine is released into the synaptic cleft.

Acetylcholine binds to its receptors on the junctional folds.

Junctional folds become depolarized.

Action potential is initiated on the sarcolemma.  

Explanation:

When the electrical signal (action potential) reaches the axon terminal it opens Ca channels that release Ca ions from the outside inside the axon terminal. Ca ions trigger the fusion of vesicle with membrane of the presynaptic cell (axon terminal). As a consequence, neurotransmitter-acetylcholine is released into the synaptic cleft. It diffuses to the postsynaptic cell and binds to its receptor (nicotinic acetylcholine receptor). The binding of acetylcholine leads to the depolarization of  the sarcolemma.

question#1

ans:

cell is the basic unit of organization of all living things. cells are often called the building block of life and it is the smallest unit of life. the study of cell is called cell biology. cell consists of cytoplasm enclosed within membrane, which contain bio-molecules such as proteins and nucleic acid.

two third of cell is water, which means that two-third of your whole body is water. the rest is the mixture of molecules, mainly proteins, lipids and carbohydrates.

question#2

ans:

organ:

an organ is a group of tissues specialized to form a functional unit. an example is the heart in animals.

organ system:

an organ system is a group of several organs whose functions are synchronized to release an effective action in a living organism. an example is digestive system.

question#3

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#4

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system—working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#5

our body works because of the interactions that happen between organs and organ systems.  

for example:  

the heart to regulate blood flow throughout the body. the blood carries oxygen and nutrients to the cells and carries carbon dioxide and waste away from the cells. body systems work together in maintaining a constant internal environment. when this balance is disrupted, the body systems may not function properly, and human health can suffer.   you start to feel bad.